{"id":534,"date":"2018-07-26T10:13:42","date_gmt":"2018-07-26T17:13:42","guid":{"rendered":"https:\/\/actionsnippet.com\/?p=3025"},"modified":"2018-07-26T10:13:42","modified_gmt":"2018-07-26T17:13:42","slug":"3d-point-to-2d-point-easy-mini-3d-engine","status":"publish","type":"post","link":"https:\/\/actionsnippet.com\/?p=534","title":{"rendered":"3d Point to 2d Point (Easy Mini 3d Engine)"},"content":{"rendered":"

Many years ago when I had just started programming I found this absolute gem by Andries Odendaal.<\/p>\n

modern es6 version<\/em><\/p>\n

\r\nlet rotX = 0, rotY = 0,\r\n    perspective = 500, \r\n    depth,\r\n    currX, currY;\r\n\/\/ learned something like this at Andries Odendaal's www.wireframe.co.za \r\nfunction point3d(x, y, z) {\r\n    let cosX = Math.cos(rotX),\r\n        cosY = Math.cos(rotY),\r\n        sinX = Math.sin(rotX),\r\n        sinY = Math.sin(rotY),\r\n        posX, posY, posZ;\r\n   \r\n    posZ = z * cosX - x * sinX,\r\n    posX = z * sinX + x * cosX,\r\n    posY = y * cosY - posZ * sinY,\r\n    posZ = y * sinY + posZ * cosY;\r\n    \r\n    depth = 1 \/ (posZ \/ perspective + 1);\r\n    currX = posX * depth;\r\n    currY = posY * depth;\r\n \r\n    return [ currX, currY, depth ];\r\n}\r\n<\/pre>\n
Here’s is an example of it in action:<\/p>\n